 * {
     margin: 0;
     padding: 0;
     box-sizing: border-box;
     font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
 }

 :root {
     --bilibili-blue: #00A1D6;
     --bilibili-pink: #FB7299;
     --light-bg: #FFFFFF;
     --sidebar-bg: #F8F9FA;
     --card-bg: #FFFFFF;
     --text-dark: #212529;
     --text-gray: #6C757D;
     --border-color: #E9ECEF;
     --hover-bg: #F1F3F5;
 }

 body {
     background-color: var(--light-bg);
     color: var(--text-dark);
     display: flex;
     min-height: 100vh;
 }

 /* 左侧导航栏 */
 .sidebar {
     width: 220px;
     background-color: var(--sidebar-bg);
     padding: 20px 0;
     display: flex;
     flex-direction: column;
     border-right: 1px solid var(--border-color);
     position: relative;
     box-shadow: 0 0 10px rgba(0, 0, 0, 0.05);
 }

 .logo {
     padding: 0 20px 20px;
     border-bottom: 1px solid var(--border-color);
     margin-bottom: 20px;
     display: flex;
     align-items: center;
     gap: 10px;
 }

 .logo img {
     height: 40px;
 }

 .logo-text {
     font-size: 20px;
     font-weight: bold;
     background: linear-gradient(90deg, var(--bilibili-blue), var(--bilibili-pink));
     -webkit-background-clip: text;
     -webkit-text-fill-color: transparent;
 }

 /* 投稿按钮 */
 .upload-btn {
     background: var(--bilibili-blue);
     color: white;
     border: none;
     border-radius: 6px;
     padding: 12px 20px;
     margin: 0 20px 20px;
     display: flex;
     align-items: center;
     justify-content: center;
     font-weight: bold;
     cursor: pointer;
     transition: all 0.3s;
     box-shadow: 0 4px 12px rgba(0, 161, 214, 0.2);
     text-decoration: none;
 }

 .upload-btn i {
     margin-right: 8px;
     font-size: 16px;
 }

 .upload-btn:hover {
     background: #0088b3;
     transform: translateY(-2px);
     box-shadow: 0 6px 15px rgba(0, 161, 214, 0.25);
 }

 .upload-btn:active {
     transform: translateY(0);
     box-shadow: 0 3px 8px rgba(0, 161, 214, 0.2);
 }

 .nav-item {
     padding: 12px 25px;
     display: flex;
     align-items: center;
     color: var(--text-gray);
     text-decoration: none;
     transition: all 0.3s;
     font-size: 15px;
     border-left: 3px solid transparent;
 }

 .nav-item i {
     margin-right: 12px;
     font-size: 18px;
     width: 24px;
     text-align: center;
 }

 .nav-item:hover,
 .nav-item.active {
     background: var(--hover-bg);
     color: var(--bilibili-blue);
     border-left: 3px solid var(--bilibili-blue);
 }

 .nav-item.active {
     color: var(--bilibili-blue);
     font-weight: 500;
 }

 /* 主内容区 */
 .main-content {
     flex: 1;
     display: flex;
     flex-direction: column;
     background: var(--light-bg);
 }

 /* 顶部工具栏 */
 .top-bar {
     height: 60px;
     background-color: var(--sidebar-bg);
     display: flex;
     align-items: center;
     justify-content: space-between;
     padding: 0 25px;
     border-bottom: 1px solid var(--border-color);
     box-shadow: 0 2px 5px rgba(0, 0, 0, 0.03);
 }

 .search-box {
     position: relative;
     width: 300px;
 }

 .search-box input {
     width: 100%;
     background: var(--card-bg);
     border: 1px solid var(--border-color);
     border-radius: 20px;
     padding: 8px 15px 8px 40px;
     color: var(--text-dark);
     font-size: 14px;
     transition: all 0.3s;
 }

 .search-box input:focus {
     outline: none;
     border-color: var(--bilibili-blue);
     box-shadow: 0 0 0 3px rgba(0, 161, 214, 0.1);
 }

 .search-box i {
     position: absolute;
     left: 15px;
     top: 50%;
     transform: translateY(-50%);
     color: var(--text-gray);
 }

 .user-actions {
     display: flex;
     align-items: center;
 }

 .notification {
     position: relative;
     margin-right: 25px;
     font-size: 18px;
     color: var(--text-gray);
     cursor: pointer;
     transition: color 0.2s;
 }

 .notification:hover {
     color: var(--bilibili-blue);
 }

 /*.notification::after {
            content: "3";
            position: absolute;
            top: -5px;
            right: -10px;
            background: var(--bilibili-pink);
            color: white;
            font-size: 10px;
            width: 18px;
            height: 18px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
        }*/

 .user-profile {
     display: flex;
     align-items: center;
     cursor: pointer;
     padding: 5px 10px;
     border-radius: 20px;
     transition: background 0.2s;
 }

 .user-profile:hover {
     background: var(--hover-bg);
 }

 .user-avatar {
     width: 36px;
     height: 36px;
     border-radius: 50%;
     background: linear-gradient(45deg, var(--bilibili-blue), var(--bilibili-pink));
     margin-right: 10px;
     display: flex;
     align-items: center;
     justify-content: center;
     color: white;
     font-weight: bold;
     font-size: 18px;
 }

 .username {
     font-size: 14px;
     color: var(--text-dark);
     font-weight: 500;
 }

 /* 内容区域 */
 .content-area {
     padding: 25px;
     flex: 1;
     overflow-y: auto;
     background: #f0f2f5;
 }

 .section-title {
     font-size: 20px;
     margin-bottom: 20px;
     display: flex;
     align-items: center;
     color: var(--text-dark);
 }

 .section-title i {
     margin-right: 10px;
     color: var(--bilibili-blue);
 }

 .stats-cards {
     display: grid;
     grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
     gap: 20px;
     margin-bottom: 30px;
 }

 .stat-card {
     background: var(--card-bg);
     border-radius: 8px;
     padding: 20px;
     display: flex;
     flex-direction: column;
     transition: transform 0.3s;
     box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
     border: 1px solid var(--border-color);
 }

 .stat-card:hover {
     transform: translateY(-5px);
     box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
 }

 .stat-title {
     color: var(--text-gray);
     font-size: 14px;
     margin-bottom: 10px;
 }

 .stat-value {
     font-size: 28px;
     font-weight: bold;
     margin-bottom: 5px;
 }

 .stat-change {
     font-size: 13px;
     color: #4CAF50;
 }

 .stat-change.negative {
     color: #F44336;
 }

 /* 内容模块 */
 .content-modules {
     display: grid;
     grid-template-columns: 2fr 1fr;
     gap: 25px;
 }

 .module-card {
     background: var(--card-bg);
     border-radius: 8px;
     padding: 20px;
     margin-bottom: 25px;
     box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
     border: 1px solid var(--border-color);
 }

 .module-header {
     display: flex;
     justify-content: space-between;
     align-items: center;
     margin-bottom: 20px;
 }

 .module-title {
     font-size: 18px;
     font-weight: bold;
     color: var(--text-dark);
 }

 .view-all {
     color: var(--bilibili-blue);
     font-size: 14px;
     text-decoration: none;
     font-weight: 500;
     transition: opacity 0.2s;
 }

 .view-all:hover {
     opacity: 0.8;
 }

 .video-list {
     display: flex;
     flex-direction: column;
 }

 .video-item {
     display: flex;
     padding: 12px 0;
     border-bottom: 1px solid var(--border-color);
 }

 .video-item:last-child {
     border-bottom: none;
 }

 .video-thumb {
     width: 160px;
     height: 90px;
     border-radius: 4px;
     background: linear-gradient(45deg, #2a5caa, #3a86cc);
     position: relative;
     margin-right: 15px;
     overflow: hidden;
     flex-shrink: 0;
 }

 .video-duration {
     position: absolute;
     bottom: 5px;
     right: 5px;
     background: rgba(0, 0, 0, 0.7);
     color: white;
     font-size: 12px;
     padding: 2px 5px;
     border-radius: 2px;
 }

 .video-info {
     flex: 1;
 }

 .video-title {
     font-size: 15px;
     margin-bottom: 8px;
     font-weight: 500;
     color: var(--text-dark);
 }

 .video-stats {
     display: flex;
     font-size: 13px;
     color: var(--text-gray);
 }

 .stat-item {
     margin-right: 15px;
     display: flex;
     align-items: center;
 }

 .stat-item i {
     margin-right: 5px;
     font-size: 12px;
 }

 .action-buttons {
     display: flex;
     flex-direction: column;
     justify-content: center;
 }

 .action-btn {
     background: var(--bilibili-blue);
     color: white;
     border: none;
     border-radius: 4px;
     padding: 6px 12px;
     font-size: 13px;
     cursor: pointer;
     margin-bottom: 8px;
     transition: background 0.3s;
     min-width: 80px;
 }

 .action-btn:hover {
     background: #0088b3;
 }

 .action-btn.edit {
     background: var(--card-bg);
     border: 1px solid var(--border-color);
     color: var(--text-gray);
 }

 .action-btn.edit:hover {
     background: var(--hover-bg);
     border-color: var(--bilibili-blue);
     color: var(--bilibili-blue);
 }

 /* 数据图表 */
 .chart-container {
     height: 250px;
     background: var(--light-bg);
     border-radius: 4px;
     position: relative;
     display: flex;
     align-items: flex-end;
     padding: 15px;
     border: 1px solid var(--border-color);
 }

 .chart-bar {
     flex: 1;
     margin: 0 5px;
     display: flex;
     flex-direction: column;
     align-items: center;
 }

 .bar-value {
     background: linear-gradient(to top, var(--bilibili-blue), #3a86cc);
     width: 100%;
     border-radius: 3px 3px 0 0;
 }

 .bar-label {
     margin-top: 8px;
     font-size: 12px;
     color: var(--text-gray);
 }

 /* 活动卡片 */
 .activity-card {
     background: linear-gradient(135deg, var(--card-bg), #f5f7fa);
     border-radius: 8px;
     padding: 20px;
     margin-bottom: 25px;
     border: 1px solid var(--border-color);
     box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
 }

 .activity-title {
     font-size: 18px;
     margin-bottom: 15px;
     color: var(--bilibili-blue);
     font-weight: bold;
 }

 .activity-desc {
     font-size: 14px;
     color: var(--text-gray);
     margin-bottom: 20px;
     line-height: 1.6;
 }

 .activity-stats {
     display: flex;
     margin-bottom: 20px;
     background: var(--hover-bg);
     border-radius: 6px;
     padding: 5px;
 }

 .activity-stat {
     flex: 1;
     text-align: center;
     padding: 10px;
 }

 .activity-stat-value {
     font-size: 24px;
     font-weight: bold;
     margin-bottom: 5px;
     color: var(--text-dark);
 }

 .activity-stat-label {
     font-size: 13px;
     color: var(--text-gray);
 }

 .btn-primary {
     background: var(--bilibili-pink);
     color: white;
     border: none;
     border-radius: 4px;
     padding: 10px 20px;
     font-size: 14px;
     cursor: pointer;
     width: 100%;
     transition: background 0.3s;
     font-weight: 500;
 }

 .btn-primary:hover {
     background: #e65a82;
 }

 /* 投稿模态框 */
 .modal {
     display: none;
     position: fixed;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
     background: rgba(0, 0, 0, 0.7);
     z-index: 1000;
     align-items: center;
     justify-content: center;
 }

 .modal-content {
     background: var(--card-bg);
     width: 600px;
     max-width: 90%;
     border-radius: 10px;
     overflow: hidden;
     box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
 }

 .modal-header {
     background: var(--bilibili-blue);
     padding: 15px 20px;
     display: flex;
     justify-content: space-between;
     align-items: center;
 }

 .modal-title {
     color: white;
     font-size: 18px;
     font-weight: bold;
 }

 .close-btn {
     background: none;
     border: none;
     color: white;
     font-size: 24px;
     cursor: pointer;
     padding: 0 10px;
     transition: color 0.2s;
 }

 .close-btn:hover {
     color: #f0f0f0;
 }

 .modal-body {
     padding: 20px;
 }

 .form-group {
     margin-bottom: 20px;
 }

 .form-group label {
     display: block;
     margin-bottom: 8px;
     font-weight: 500;
     color: var(--text-gray);
 }

 .form-group input,
 .form-group textarea,
 .form-group select {
     width: 100%;
     padding: 10px;
     background: var(--light-bg);
     border: 1px solid var(--border-color);
     border-radius: 4px;
     color: var(--text-dark);
     font-size: 14px;
     transition: border 0.3s;
 }

 .form-group input:focus,
 .form-group textarea:focus,
 .form-group select:focus {
     outline: none;
     border-color: var(--bilibili-blue);
     box-shadow: 0 0 0 3px rgba(0, 161, 214, 0.1);
 }

 .form-group textarea {
     min-height: 100px;
     resize: vertical;
 }

 .file-upload {
     border: 2px dashed var(--border-color);
     border-radius: 8px;
     padding: 30px;
     text-align: center;
     cursor: pointer;
     transition: all 0.3s;
     background: var(--light-bg);
 }

 .file-upload:hover {
     border-color: var(--bilibili-blue);
     background: rgba(0, 161, 214, 0.05);
 }

 .file-upload i {
     font-size: 40px;
     color: var(--bilibili-blue);
     margin-bottom: 15px;
 }

 .file-upload p {
     color: var(--text-gray);
     margin-bottom: 10px;
 }

 .modal-footer {
     padding: 15px 20px;
     background: var(--sidebar-bg);
     display: flex;
     justify-content: flex-end;
     border-top: 1px solid var(--border-color);
 }

 .btn-submit {
     background: var(--bilibili-blue);
     color: white;
     border: none;
     border-radius: 4px;
     padding: 10px 20px;
     font-weight: bold;
     cursor: pointer;
     transition: background 0.3s;
 }

 .btn-submit:hover {
     background: #0088b3;
 }

 /* 响应式调整 */
 @media (max-width: 992px) {
     .content-modules {
         grid-template-columns: 1fr;
     }

     .sidebar {
         width: 70px;
     }

     .nav-item span {
         display: none;
     }

     .nav-item i {
         margin-right: 0;
         font-size: 20px;
     }

     .logo-text {
         display: none;
     }

     /* 小屏幕下投稿按钮样式 */
     .upload-btn {
         padding: 12px 0;
         margin: 0 15px 15px;
     }

     .upload-btn span {
         display: none;
     }

     .upload-btn i {
         margin-right: 0;
         font-size: 20px;
     }
 }

 @media (max-width: 768px) {
     .stats-cards {
         grid-template-columns: 1fr;
     }

     .search-box {
         width: 150px;
     }
 }
 .video-thumb {
    width: 160px;
    height: 90px;
    border-radius: 4px;
    overflow: hidden;
    position: relative;
    background-color: #f5f5f5; /* 默认背景色，封面加载失败时显示 */
}

.video-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.video-duration {
    position: absolute;
    bottom: 4px;
    right: 4px;
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    padding: 2px 4px;
    border-radius: 2px;
    font-size: 10px;
    line-height: 1;
}